Single source of truth: __version__ in daybook_project/__init__.py, starting
at 0.1.0. Surfaced in two places from that constant:
- Settings -> About page (logo, name, version, description), in the settings
nav and linked from the gear menu.
- GET /api/capabilities now includes "version", so the deploy agent / tester
can confirm which version is actually running.
Release flow: bump __version__, commit, `git tag vX.Y.Z`, push tag, deploy.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>